// towers of hanoi in Fun+− +− def hanoi(n, a, b, c) =+− if n != 0 then {+− hanoi (n - 1) a c b;+− print_endline ("Move disk from pole " ^ (show a) ^ " to pole " ^ (show b));+− hanoi (n - 1) c b a+− } else write("")+− +− impure $ hanoi 4 1 2 3;;+−